Lower Serum Progesterone Concentrations Research Articles

Spironolactone metabolite causes falsely increased progesterone in the Abbott Architect immunoassay

BackgroundImmunoassays are important for routine clinical testing and medical diagnosis. However, they are limited by cross-reactivity especially at low analyte concentrations. There is a critical need to investigate compounds that can interfere with immunoassays. Herein, we describe the identification of canrenone, a spironolactone metabolite that falsely increases progesterone concentrations on the Abbott Architect i2000 Immunoassay. MethodsSerum samples and assay diluents were spiked with spironolactone or canrenone and progesterone concentrations were measured on the Architect i2000 and Immulite XPi immunoassay platforms. Blood samples from patients taking spironolactone were analyzed with liquid chromatography-tandem mass spectrometry to evaluate the intrinsic response of progesterone concentrations to the presence of canrenone. ResultsWe measured approximately 10-fold higher progesterone concentrations on the Abbott Architect i2000 compared to reference immunoassay analyzers (Siemens Immulite XPi and Roche Cobas e601/602), suggesting an analytical error which is unique to the Architect i2000 antibody and/or assay conditions. By measuring serum progesterone after addition of spironolactone or canrenone to serum samples, we found that canrenone falsely increased progesterone on the Architect i2000 immunoassay. However, this interference was more pronounced at low serum progesterone concentrations. Moreover, a strong positive correlation was seen between canrenone and measured serum progesterone concentrations. ConclusionsOur investigations are important for individuals who require progesterone measurements using the Architect i2000 immunoassay, especially because it is unlikely for clinicians to order canrenone measurements alongside progesterone measurements for individuals taking spironolactone. Further research is needed to determine whether canrenone can influence progesterone measurements on other immunoassay systems.

Individualized luteal phase support using additional oral dydrogesterone in artificially prepared frozen embryo transfer cycles: is it beneficial?

Research questionDoes additional supplementation with oral dydrogesterone improve reproductive outcomes in patients with low serum progesterone concentrations on the day of frozen embryo transfer (FET) after artificial (HRT) endometrial preparation? DesignRetrospective, single-centre cohort study including 694 unique patients performing single blastocyst transfer in an HRT cycle. For luteal phase support, intravaginal micronized vaginal progesterone (MVP, 400 mg twice daily) was administered. Serum progesterone concentrations were assessed prior to FET and outco-mes were compared among patients with normal serum progesterone (≥8.8 ng/ml) continuing the routine protocol and patients with low serum progesterone (<8.8 ng/ml) who received additional oral dydrogesterone supplementation (10 mg three times daily) from the day after FET onwards. Primary outcome was live birth rate (LBR), with a multivariate regression model correcting for relevant confounders. ResultsNormal serum progesterone concentrations were observed in 547/694 (78.8%) of patients who continued only MVP as planned, whereas low (<8.8 ng/ml) serum progesterone concentrations were detected in 147/694 (21.2%) patients who received additional oral dydrogesterone supplementation on top of MVP from the day after FET onwards. LBR was comparable between both groups: 37.8% for MVP-only versus 38.8% for MVP+OD (P = 0.84). The multivariate logistic regression model indicated that LBR was not significantly associated with the investigated approaches (adjusted odds ratio 1.01, 95% confidence interval 0.69–1.47, P = 0.97). ConclusionsThe current findings suggest that additional oral dydrogesterone supplementation in patients with low serum progesterone concentrations at the moment of transfer could have the potential to rescue reproductive outcomes in HRT–FET cycles. This field of research, however, remains hampered by the absence of randomized controlled trials.

The addition of dydrogesterone improves the outcomes of pregnant women with low progesterone levels when receiving vaginal progesterone alone as luteal support in HRT-FET cycles.

Vaginal progesterone (VP) alone has been used as luteal support (LS) in HRT-FET cycles without measuring serum progesterone concentrations (SPC) because it can achieve adequate intrauterine progesterone levels. However, several reports showed that the co-administration of progestin produced better outcomes than VP alone. We tried to address this discrepancy, focusing on SPC. VP was given to 180 women undergoing HRT-FET. We measured SPC when pregnancy was diagnosed on day 14 of LS. We compared assisted reproductive technology outcomes between VP alone versus VP + dydrogesterone (D). When using VP alone, average SPC in the miscarriage cases (9.6ng/mL) were significantly lower compared with the ongoing pregnancy (OP) cases (14.7ng/mL). The cut-off value for progesterone, 10.7ng/mL, was a good predictor for the subsequent course of the pregnancy. Of 76 women receiving D ± VP from the start of LS and achieving a pregnancy, the numbers of OP were 44 (84.6%) in SPC≥ 10.7ng/mL and 20 (83.3%) in SPC ≤ 10.7ng/mL with no significant difference. VP alone resulted in lower SPC in some pregnant women in HRT-FET cycles and exhibited a lower OP rate. The co-administration of D improved an OP rate of low progesterone cases to the level comparable with non-low progesterone cases.

RELATIONSHIP BETWEEN ROUTE OF PROGESTERONE SUPPLEMENTATION, SERUM PROGESTERONE CONCENTRATION, AND LIVE BIRTH FROM VITRIFIED-WARMED BLASTOCYST TRANSFERS: SECONDARY ANALYSES OF A RANDOMIZED CONTROLLED TRIAL (RCT)

Recent RCT data indicate that programmed endometrial preparation regimens inclusive of intramuscular progesterone (IMP) are superior to regimens using vaginal progesterone (VP) only, in terms of live birth (LB) from frozen embryo transfer (FET) (1). Studies suggest inferior FET outcomes with lower serum progesterone concentration (P). A recent meta-analysis suggested P <10ng/mL as a negative prognosticator. However, most published analyses relied upon FET with VP only (2). It remains unclear whether P is associated with lower LB when IMP is used.

The importance of serum progesterone concentration at embryo transfer day and effect of rescue additional progesterone during programmed artificial frozen embryo transfer cycles

Research questionWhat is the efficacy and possible positive effect of additional rescue subcutaneous (s.c.) progesterone therapy for restoration of progesterone concentration on embryo transfer day and pregnancy rates during programmed artificial frozen embryo transfer (FET) cycles with vaginal progesterone tablet plus i.m. progesterone? DesignMulticentre prospective cohort study (NCT04769401) including a total of 238 programmed artificial FET between February 2021 and September 2021. Patients were divided into ≥10 ng/ml and <10 ng/ml according to serum progesterone concentrations on embryo transfer day; 25 mg of s.c. progesterone was added to patients with <10 ng/ml; blood samples were taken 2 days later. The primary outcome was the ongoing pregnancy rate. ResultsThe proportion of patients having ≥10 ng/ml serum progesterone concentrations on embryo transfer day was 70.7%. There was no statistically significant difference with regard to cumulative pregnancy rate, ongoing pregnancy rate and miscarriage between the groups (55.4% versus 61.5%, P = 0.4; 78.2% versus 72.5% per pregnancy, P = 0.5; 21.8% versus 27.5%, P = 0.5, respectively, ≥10 ng/ml and <10 ng/ml). Eighty-three per cent of patients with low serum progesterone concentrations on embryo transfer day reached an adequate progesterone concentration with rescue s.c. progesterone treatment; 90% of pregnancy rates in patients with serum progesterone concentrations <10 ng/ml on embryo transfer day were in patients who reached adequate serum progesterone concentrations with daily rescue s.c. progesterone treatment. ConclusionsThe measurement of serum progesterone concentrations on embryo transfer day may create the opportunity for rescue progesterone administration on that day for patients who fail to reach adequate serum progesterone concentrations, achieving similar pregnancy rates without cancellation of the cycle.

Subcutaneous luteal phase progesterone rescue rectifies ongoing pregnancy rates in hormone replacement therapy vitrified–warmed blastocyst transfer cycles

Research questionWill luteal phase rescue with additional progesterone increase serum progesterone concentrations and improve reproductive outcomes in patients with low serum progesterone concentrations undergoing hormone replacement therapy (HRT) cycles? DesignCase–control study including 40 consecutive patients with serum progesterone concentrations <8.75 ng/ml on the 5th day of progesterone supplementation who underwent rescue with a daily bolus of 25 mg s.c. progesterone, starting on the afternoon of the 5th day of progesterone administration. For every patient who underwent progesterone rescue, three patients matched by age, body mass index, number of previous attempts and number of blastocysts transferred, with serum progesterone concentration >8.75 ng/ml on the 5th day of progesterone administration served as controls (n = 120). The main outcome measure was ongoing pregnancy rate (OPR). ResultsBaseline demographic features and embryological data of the rescue and control groups were comparable. As expected, the mean serum progesterone concentration was lower in the rescue group on the 5th day of progesterone administration (7.84 ± 0.92 versus 15.32 ± 5.02 ng/ml; P < 0.001). Following rescue, the mean serum progesterone concentration on the day of vitrified–warmed embryo transfer (6th day of progesterone administration) was 33.43 ± 10.83 ng/ml (range 14.61–82.64 ng/ml), and the OPR of the rescue and control groups were comparable. ConclusionsIn patients undergoing HRT vitrified–warmed blastocyst transfer with serum progesterone concentrations lower than 8.75 ng/ml 1 day prior to the scheduled embryo transfer (6th day of progesterone administration), additional supplementation with a 25 mg s.c. daily progesterone dose seems to rescue the cycle, resulting in OPR comparable to those of patients with serum progesterone >8.75 ng/ml.

Superovulatory Response and Progesterone Profile in Murrah Buffaloes (Bubalus bubalis) Pretreated with GnRH Agonist

Background: Limited elite buffalo population need to be propagated at faster rate to sustain the dairy industry in India. Faster propagation could be achieved through embryo transfer technology. Low serum progesterone concentrations during the start of superstimulatory treatment is major factor that hampers the success of multiple ovulation embryo transfer (MOET) in buffaloes. This study evaluated the effect of GnRH pretreatment before superovulatory regimen on progesterone profile, superovulation and correlation of progesterone with superstimulatory parameter in Murrah buffaloes. Methods: Buffaloes (n=27) were superstimulated using 600 mg Folltropin and divided into three groups on basis of pretreatment: Group I and group II were pretreated with GnRH @ 10 µg and 06 µg, respectively while no pretreatment was subjected in group III (control). Progesterone hormone concentration, superovulatory response, ovulation rate, embryo recovery were recorded. Result: Our study revealed that superovulatory response was non-significantly different in all three groups and ranged from 6-8 in terms of number of corpus luteum (CL). Average number of recovered embryos in this study was nearly 2.0. A positive correlation between progesterone concentrations at the initiation of FSH treatment with number of CL and embryo recovery was observed. The study indicated that GnRH pretreatment before superstimulation improve the serum progesterone concentration, superovulatory response and embryo recovery in Murrah buffaloes.

The Neglected Luteal Phase after Natural Conception: Rescue by Early Progesterone Supplementation

Background: Luteal phase deficiency (LPD) was recognized as a potential cause of infertility well before the first attempts at ovarian stimulation and in vitro fertilization (IVF). However, in the subsequent IVF era, the fact that LPD is particularly frequent in the context of ovarian stimulation has driven the attention to LPD almost exclusively to stimulated cycles. Here we re-assess the role of LPD as the primary cause of infertility and suggest a possible solution.Patients and methods: This study involves 12 young couples with unexplained infertility who attended our clinic for an assisted reproduction attempt. All of the female partners had low serum progesterone concentrations on day 21 of their menstrual cycle, in spite of the presence on an apparently functional corpus luteum. The female patients underwent repeated ultrasound scans during three subsequent cycles to determine the day of spontaneous ovulation. They were counselled to have frequent sexual intercourse when the dominant follicle reached the size of &gt;17 mm, and progesterone was administered daily, by vaginal route, in all of them beginning with the day on which ovulation had been confirmed.Results: Out of the 12 women included in this study, six became pregnant naturally during one of the three progesterone-supplemented cycles. Progesterone supplementation was discontinued progressively, based on repeated serum progesterone determinations during the early pregnancy. All of the pregnancies were singleton. One of them ended in a miscarriage, while the others went to term, resulting in the birth of five normal children.Conclusions: Our data suggest that LPD during natural ovulatory cycles may be more frequent than believed. In the present study, no other apparent causes of infertility were detected. In such cases, assisted reproduction techniques can be avoided and replaced by individualized progesterone supplementation during the early luteal phase.

GnRH agonist treatment of luteal phase deficiency in HCG-triggered IVF cycles: a matched case-control study.

This study aimed to identify women with IVF failure associated with low serum progesterone levels after embryo transfer in HCG-triggered cycles and to evaluate the effects of gonadotrophin-releasing hormone (GnRH) agonist, administered after embryo transfer, on serum progesterone and pregnancy outcomes in these cases. Fifty women who failed to achieve an ongoing clinical pregnancy and had abnormally low luteal-phase serum progesterone concentrations in their first IVF attempt were assigned to two matched groups in their subsequent attempt. Twenty-five women were treated with the original protocol plus14 daily injections of GnRH agonist, beginning on the day of oocyte recovery, in their second IVF attempt (group 1). These women were matched to 25 women with the same characteristics and outcomes in their first IVF attempt who underwent the second IVF attempt without the use of GnRH agonist after embryo transfer (group 2). In both groups, the two sequential attempts were compared for serum progesterone concentration 14 days after oocyte recovery and pregnancy outcome. The patients in group 1 had significantly higher progesterone levels 14 days after oocyte recovery in the second attempt compared with the first attempt (P < 0.001), and 12 (48%) of them achieved clinical pregnancy and birth. No significant differences in pregnancy outcome or in the serum progesterone concentration were observed between the first and the second attempt in group 2. In patients with luteal phase deficiency, the administration of GnRH agonist after embryo transfer increases serum progesterone concentration and improves the chance of pregnancy and birth.

Effects of deficiency and surplus dietary threonine on reproductive performance of primiparous pregnant gilts.

Dietary threonine imbalance is known to impair reproductive performances of gestating sows, but the underlying mechanisms are largely unknown. In this study, effects of deficiency and surplus dietary threonine during gestation on reproductive performance, serum metabolites and hormones concentration, and colostral nutrient and immunoglobulin contents of primiparous sows were investigated. Ninety primiparous pregnant gilts were assigned to one of the three dietary treatments with different standardized ileal digestible threonine/lysine ratios at 0.59, 0.72 and 0.85, which represented deficient (DT), adequate (AT) and surplus (ST) dietary threonine concentration respectively. Maternal body weight gain from day 80-110 of gestation was highest (p<.05) for gilts fed AT than for gilts fed DT or ST. On days 30 and 110, serum threonine concentration increases in a dose-dependent manner with the increasing of dietary threonine concentration in (p<.01), serum urea nitrogen concentration was lower (p<.01) in gilts fed AT than DT or ST, and serum insulin-like growth factor-I (IGF-I) was lowest (p<.05) for gilts fed DT. On day 110, gilts fed AT had lower serum progesterone concentration but higher concentrations of serum prolactin (p<.05) compared to DT and ST. Concentration of colostral immunoglobulin A and G from gilts fed DT was lower (p<.05) compared with gilts fed AT or ST. In conclusion, gilts with the adequate threonine intake were more able to conserve dietary amino acids to support foetal and maternal tissue gain. Deficient or ST threonine intake may induce a delay in changes in progesterone and prolactin concentrations during the prepartum period impeding the transition from pregnancy to lactation.

Accuracy of a Direct Progesterone Immunoassay.

Beyond the established role of serum progesterone measurement in the luteal phase of menstrual cycle to confirm recent ovulation, it is also increasingly used to detect premature luteinization during in vitro fertilization (IVF) hyperstimulation, where late follicular phase increase in serum progesterone is reportedly associated with adverse pregnancy outcomes. Virtually all serum progesterone measurements in clinical and IVF practice use direct, nonextraction immunoassays, often in multiplex, high-throughput platform assays optimized for high, postovulatory, midluteal phase serum progesterone concentrations. However, the performance of direct progesterone immunoassays for smaller increases is not established. We studied 254 women undergoing IVF hyperstimulation with serum progesterone around the time of human chorionic gonadotropin (hCG) administration, measured in each sample by a direct progesterone immunoassay (Beckman Coulter Access) and by LC-MS. Immunoassay overestimated serum progesterone in almost every sample with an increasingly high variability and deviation at lower concentrations (immunoassay <5 nmol/L, equivalent to LC-MS <2 nmol/L). Immunoassay consistently overestimates serum progesterone levels so that low measurements (immunoassay <5 nmol/L) are too inaccurate to be used quantitatively. The utility of higher serum progesterone measurements by immunoassay and serum progesterone and other steroids measured by multiplex LC-MS profiling in predicting IVF pregnancy outcomes warrants further investigation. There is a need for caution in clinical diagnosis of premature luteinization based on increased late follicular phase serum progesterone measurements using direct progesterone immunoassay that consistently overestimates low serum progesterone concentrations.

Effect of progesterone concentrations, follicle diameter, timing of artificial insemination, and ovulatory stimulus on pregnancy rate to synchronized artificial insemination in postpubertal Nellore heifers

Two experiments were designed to evaluate the effects of treatments with low versus high serum progesterone (P4) concentrations on factors associated with pregnancy success in postpubertal Nellore heifers submitted to either conventional or fixed timed artificial insemination (FTAI). Heifers were synchronized with a new controlled internal drug release device (CIDR; 1.9 g of P4 [CIDR1]) or a CIDR previously used for 18 days (CIDR3) plus 2 mg of estradiol (E2) benzoate on Day 0 and 12.5 mg of prostaglandin F2α on Day 7. In experiment 1 (n = 723), CIDR were removed on Day 7 or 9 and heifers were inseminated after estrus detection. In experiment 2 (n = 1083), CIDR were all removed on Day 9 and FTAI was performed either 48 hours later in heifers that received E2 cypionate (ECP) on Day 9 (0.5 mg; E48) or 54 or 72 hours later in conjunction with administration of GnRH (100 μg; G54 or G72). Synchronization with CIDR1 resulted in greater serum P4 concentrations and smaller follicle diameters on Days 7 and 9 in both experiments. In experiment 1, treatment with CIDR for 9 days decreased the interval from CIDR removal to estrus (Day 7, 3.76 ± 0.08 days vs. Day 9, 2.90 ± 0.07; P < 0.01) and improved conception (Day 7, 57.1% vs. Day 9, 65.8%; P = 0.05) and pregnancy rates (Day 7, 37.6% vs. Day 9, 45.3%; P = 0.04). In experiment 2, treatment with ECP improved (P < 0.01) the proportion of heifers in estrus (E48, 40.9%a; G54, 17.1%c; and G72, 32.0%b), but the pregnancy rate was not affected (P = 0.64) by treatments (E48, 38.8%; G54, 35.5%; G72, 37.5%). Synchronization with CIDR3 increased follicle diameter at FTAI (CIDR1, 11.07 ± 0.10 vs. CIDR3, 11.61 ± 0.10 mm; P < 0.01), ovulation rate (CIDR1, 82.8% vs. CIDR3, 88.0%; P < 0.01) and did not affect conception (CIDR1, 42.2 vs. CIDR3, 45.1%; P = 0.38) or pregnancy rates (CIDR1, 34.7 vs. CIDR3, 39.4%; P = 0.11). In conclusion, length of treatment with P4 affected the fertility of heifers bred based on estrus detection. When the heifers were submitted to FTAI protocol, follicle diameter at FTAI (≤10.7 mm, 23.6%; 10.8–15.7 mm, 51.5%; ≥15.8 mm, 30.0%; P < 0.01) was the main factor that affected conception and pregnancy rates.

Ovarian responses and pregnancy rate with previously used intravaginal progesterone releasing devices for fixed-time artificial insemination in sheep

The objective was to determine serum progesterone concentrations, ovarian responses, and pregnancy rate in sheep inseminated following a short-term protocol (6 days of treatment) with a previously used controlled internal drug release-G (CIDR-G) device. In experiment 1, 30 ewes were put on a short-term protocol using a CIDR-G of first use (new devices, N = 10), second use (previously used for 6 days, N = 10), or third use (previously used twice for 6 days, N = 10). All ewes were given prostaglandin F2α (10 mg dinoprost) and eCG (300 IU) im at device withdrawal. Mean serum progesterone concentrations were greater for ewes treated with new versus reused devices (P < 0.05), but there were no significant effects on ovarian follicular development, namely: proportion of ewes that reached ovulation/treated ewes (8/10, 9/10, and 10/10); day of emergence of the ovulatory follicle (2.9 ± 1.8, 1.8 ± 2.4, and 2.5 ± 1.1 days after CIDR-G insertion); and lifespan of the ovulatory follicle (5.4 ± 1.8, 6.5 ± 2.2, and 5.6 ± 1.0 days) for devices of first, second, and third use, respectively. The proportion of ewes that ovulated from a new follicle emerging after CIDR-G insertion was 100% (10/10) with new devices, and 77.8% (7/9) and 80% (8/10) with devices used two and three times, respectively (P = not significant). In experiment 2, ewes (N = 319) received the short-term protocol as in experiment 1, using CIDR-G of first or third use (N = 158 and N = 161, respectively) for 6 days, with prostaglandin F2α and eCG given im at device withdrawal. Intrauterine (laparoscopy) fixed-time AI with fresh semen (100 × 106 sperm) was done 52 to 57 hours after device withdrawal. Pregnancy rates were 80.4% (127/158) and 71.4% (115/161) for devices of first and third use, respectively (P = 0.06). We concluded that the CIDR-G with short-term protocol was effective for estrous synchronization and ovulation, with lower serum progesterone concentrations for reused devices. Three times used CIDR-G yielded a pregnancy rate >70%, which tended to be lower than that obtained with new devices, adding evidence of the detrimental effect of low serum progesterone concentrations on fertility in sheep.

Female infertility due to anovulation and defective steroidogenesis in NPC2 deficient mice

Niemann Pick C2 (NPC2) and NPC1 proteins function cooperatively to catalyze cholesterol efflux from lysosomes. NPC1 is expressed in ovarian cells and female NPC1 mice are infertile. This work addressed for the first time the localization and function of murine NPC2 protein in the ovary. Ovarian NPC2 was localized to theca and luteal cells, which use cholesterol as a substrate to produce estradiol and progesterone, respectively. NPC2 deficient (NPC2-/-) females had abnormal estrous cycles and were infertile, with normal folliculogenesis until the antral stage, but a complete absence of corpora lutea and many zonae pellucidae remnants, indicative of anovulation. Serum estradiol was reduced and ovarian cholesterol was accumulated in NPC2-/- mice, suggesting a defect in cholesterol export from intracellular stores. After superovulation, NPC2-/- mice ovulated less eggs than their wild type littermates, showed ovaries with less corpora lutea and numerous unruptured follicles, and lower serum progesterone concentration. Together, these results suggest that NPC2 participates in the traffic of ovarian cholesterol required to provide the substrate for steroid synthesis and support follicle maturation, ovulation and luteinization.

Early risk factors for miscarriage: a prospective cohort study in pregnant women

Many pregnancies are lost during early gestation, but clinicians still lack tools to recognize risk factors for miscarriage. Thus, the identification of risk factors for miscarriage during the first trimester in women with no obvious risk for a pregnancy loss was the aim of this prospective cohort trial. A total of 1098 women between gestation weeks 4 and 12 in whom no apparent signs of a threatened pregnancy could be diagnosed were recruited. Demographic, anamnestic, psychometric and biological data were documented at recruitment and pregnancy outcomes were registered subsequently. Among the cases with sufficiently available data, 809 successfully progressing pregnancies and 55 subsequent miscarriages were reported. In this cohort, risk of miscarriage was significantly increased in women at higher age (>33years), lower body mass index (≤20 kg/m 2) and lower serum progesterone concentrations (≤12 ng/ml) prior to the onset of the miscarriage. Women with subsequent miscarriage also perceived higher levels of stress/demands (supported by higher concentrations of corticotrophin-releasing hormone) and revealed reduced concentrations of progesterone-induced blocking factor. These risk factors were even more pronounced in the subcohort of women ( n = 335) recruited between gestation weeks 4 and 7. The identification of these risk factors and development of an interaction model of these factors, as introduced in this article, will help clinicians to recognize pregnant women who require extra monitoring and who might benefit from therapeutic interventions such as progestogen supplementation, especially during the first weeks of pregnancy, to prevent a miscarriage.

237. AR-mediated androgen actions are essential for normal mouse uterine growth and development but not implantation and embryo development

Recently the androgen receptor (AR) has been shown definitively to play a role in female reproduction. We generated a homozygous AR−/− female mouse using Cre/LoxP recombination for an in-frame excision of exon 3, encoding the second zinc finger essential for DNA-binding, while allowing production of an exon 3 deleted mutant AR protein which is nonfunctional as a nuclear transcription factor. AR−/− females were sub-fertile due primarily to ovulatory dysfunction (1). However, the mechanism(s) of the observed sub-fertility remains to be fully defined. To evaluate the role of AR in uterine function we carried out a morphological and function analysis of the AR−/− uterus. Uterine weights did not differ, however, AR−/− females exhibited a significant increase in uterine horn length (P &lt; 0.01), and a significant reduction in uterine diameter (P &lt; 0.01), total uterine area (P &lt; 0.01), endometrial area (P &lt; 0.05) and myometrial area (P &lt; 0.01), indicating a role for genomic AR-mediated actions in physiological uterine growth and development. Furthermore, during late pregnancy AR−/− females had significantly fewer implantation sites (P &lt; 0.01), fetuses present in utero (P &lt; 0.05) and a lower serum progesterone concentration (P &lt; 0.01). In spite of these findings, AR−/− females had normal gestational length, parturition and pup weights, as well as similar pre- and post implantation losses compared with AR+/+ females. Therefore, although AR is not essential for normal uterine reproductive function, disrupting genomic AR signalling in the uterus leads to dysfunctional uterine development which may have important long-term functional consequences for hormone dependent uterine disorders such as endometrial hyperplasia and cancer. (1) K. A. Walters et al. Endocrinology 148, 3674 (2007).

P-418: Changes in blood flow in the human corpus luteum throughout the menstrual cycle and during early pregnancy

Angiogenesis is important for development of the corpus luteum and maintenance of luteal function. To maintain progesterone production for successful pregnancy, especially when the corpus luteum is rescued by pregnancy, not only high vascularization but also adequate blood flow in the corpus luteum are necessary to provide luteal cells with large amounts of cholesterol needed for progesterone synthesis and for the delivery of progesterone to the circulation. The present study was undertaken to investigate the change in blood flow in the human corpus luteum throughout the menstrual cycle and during early pregnancy. A prospective observational study. Ninety patients with normal menstrual cycles and normal luteal function were recruited in this study. Blood flow impedances were examined in the preovulatory follicle (late follicular phase) and in the corpus luteum throughout the luteal phase (early stage of the early luteal phase:1-2 days after ovulation [D1-2], late stage of the early luteal phase:D3-4, mid-luteal phase:D5-8, late luteal phase:D10-14). Transvaginal color and pulsed Doppler ultrasound was used to evaluate perifollicular and luteal arterial blood flow and blood flow impedance was expressed as resistance index (RI). Venous blood for progesterone concentration was taken on the day of the Doppler exam during the mid-luteal phase. Eleven patients who had low serum progesterone concentrations (< 10ng/ml) in the mid-luteal phase (luteal phase defect) and 17 patients who achieved pregnancy were also recruited in this study, and their blood flow impedance were examined. RI in the preovulatory follicle decreased after ovulation. Then RI in the corpus luteum further decreased from the early stage to the late stage during the early luteal phase. RI in the corpus luteum of the mid-luteal phase was the same level as the late stage of the early luteal phase. RI in the corpus luteum thereafter increased in the late luteal phase but remained low until 7weeks of gestation during early pregnancy. A highly negative correlation was observed between the RI of the corpus luteum and serum progesterone concentrations in the mid-luteal phase. RI of the patient with luteal phase defect was significantly higher than that of the patient with normal luteal function. The present study showed the change in luteal blood flow throughout the menstrual cycle and during early pregnancy. The changes in luteal blood flow well reflect luteal angiogenesis during the formation of the corpus luteum and blood vessel regression during the corpus luteum regression. Furthermore, the present study suggests that luteal blood flow is closely associated with luteal function.

The pharmacokinetic and pharmacodynamic consequences of the co‐administration of lamotrigine and a combined oral contraceptive in healthy female subjects

To assess the pharmacokinetic and pharmacodynamic effects of co-administration of a combined oral contraceptive (ethinyloestradiol plus levonorgestrel) and lamotrigine. Over a period of 130 days, healthy female subjects took lamotrigine (titrated up to 300 mg day(-1)) and the combined oral contraceptive, either individually or as co-therapy. Plasma ethinyloestradiol and levonorgestrel concentrations were measured in the presence and absence of lamotrigine, and serum lamotrigine concentrations were measured in the presence and absence of the combined oral contraceptive. Serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), progesterone, oestradiol and sex hormone binding globulin were also determined. Of the 22 enrolled subjects, 16 had evaluable pharmacokinetic data. The mean (90% CI) ratios of lamotrigine area under the concentration-time curve from 0 to 24 h (AUC(0,24 h)) and maximum observed concentration (C(max)) of lamotrigine when it was given with the combined oral contraceptive and during monotherapy were 0.48 (0.44, 0.53) and 0.61 (0.57, 0.66), respectively. Ethinyloestradiol pharmacokinetics were unchanged by lamotrigine, the mean combined oral contraceptive + lamotrigine : combined oral contraceptive alone ratios (90% CI) of the AUC(0,24 h) and C(max) of levonorgestrel were 0.81 (0.76, 0.86) and 0.88 (0.82, 0.93), respectively. FSH and LH concentrations were increased (by 4.7-fold and 3.4-fold, respectively) in the presence of lamotrigine, but the low serum progesterone concentrations suggested that suppression of ovulation was maintained. Intermenstrual bleeding was reported by 7/22 (32%) of subjects during co-administration of lamotrigine and combined oral contraceptive. A clinically relevant pharmacokinetic interaction was observed during co-administration of a combined oral contraceptive and lamotrigine. A dosage adjustment for lamotrigine may need to be considered when these agents are co-administered. A modest decrease in the plasma concentration of levonorgestrel was also observed but there was no corresponding hormonal evidence of ovulation.

Use of Crinone∗ vaginal progesterone gel for luteal support in in vitro fertilization cycles

Objective: To investigate the efficacy and safety of intravaginal Crinone 8% (Columbia Research Laboratories, Miami, FL) versus IM progesterone for luteal phase support after IVF-ET. Design: Prospective open trial with comparison to historical controls. Setting: University hospital. Patient(s): Two hundred six women undergoing IVF-ET. Intervention(s): One hundred patients received Crinone vaginal progesterone gel (90 mg once daily) and 106 patients received IM progesterone (50 mg once daily) beginning on the evening of oocyte retrieval. Main Outcome Measure(s): Pregnancy and miscarriage rates, and midluteal serum progesterone levels. Result(s): Positive β-hCG pregnancy rates, clinical pregnancy rates per transfer, and ongoing pregnancy rates were similar for the Crinone and IM progesterone groups. Women who received Crinone had higher rates of biochemical pregnancy loss but lower rates of clinical pregnancy loss (i.e., spontaneous abortion) than women who received IM progesterone. Midluteal serum progesterone concentrations were significantly higher in the IM progesterone group (94.3 ± 8.8 ng/mL versus 57.7 ± 7.4 ng/mL). Several women who received Crinone had vaginal bleeding 11–13 days after oocyte retrieval. Conclusion(s): For all age categories, positive β-hCG and ongoing pregnancy rates were similar when Crinone or IM progesterone was given for luteal phase support in IVF-ET cycles, despite lower serum progesterone concentrations and higher rates of biochemical pregnancy loss with Crinone. Although the results of this study support the use of Crinone as an acceptable alternative for luteal support after IVF-ET, differences in bleeding patterns and rates of biochemical pregnancy loss demonstrate the need for a prospective randomized study.

Is luteal function maintained by factors other than chorionic gonadotrophin in early pregnancy?

Women with ectopic pregnancy (n = 14) and early embryonic arrest ('blighted ovum') (n = 9) were studied 16 days after conception, at a time when they were asymptomatic and serum concentrations of beta-human chorionic gonadotrophin (HCG) were in the normal range and increasing at an apparently normal rate. Serum progesterone and oestradiol concentrations were compared with those from normal women matched for gestational age and serum beta-HCG concentration whose singleton intra-uterine pregnancies proceeded normally beyond 20 weeks. Mean serum progesterone concentrations were significantly lower in the women with ectopic pregnancies than in matched controls (P < 0.002); however, there was no difference in the serum progesterone concentrations between women with blighted ova and matched controls. Statistically significant differences were not seen in serum oestradiol concentrations between either group and matched controls. Similarly there was no difference in serum progesterone or oestradiol concentrations in 20 women who conceived ectopic pregnancies and 20 women conceiving blighted ovum pregnancies and their matched intra-uterine controls when conception followed ovarian stimulation. The low serum progesterone concentrations seen in ectopic pregnancy suggest that there is a specific and selective deficiency in progesterone synthesis, which implies that factors other than HCG may influence luteal function.